Sequential color display systems generally display colors one at a time. For example, in a three-color RGB sequential color display system, a first color displayed may be red (R), followed by a second color, such as green (G), and then followed by a third color, such as blue (B). The three-color RGB sequential color display system may then continually repeat the RGB color sequence or display a different color sequence, such as BGR, RBG, and so on. The sequentially displayed colors may then be used to display images.
In a sequential color display system using a microdisplay commonly referred to as a digital micromirror device (DMD), image data corresponding to a color of light being displayed may be provided to the DMD. The image data may be used to set micromirror state (position), wherein when a micromirror is in a first state, the light may be reflected onto a display plane and when a micromirror is in a second state, the light may be reflected away from the display plane. When a different color of light is being displayed, image data corresponding to the different color of light may be provided to the DMD. A viewer's visual system generally will integrate the sequentially displayed image data into color images.
A color sequence may be designed so that colored light of various intensities (brightness) may be displayed, enabling the displaying of generally the entirety of a range of light intensities displayable by the sequential color display system. For example, a color sequence may contain a binary weighted sequence of light intensities, ranging from a light intensity of about 20 to a light intensity of about 2N, wherein 2N+1-1 is the brightest intensity of light for a given color of light producible by the sequential color display system. When there is a need to display a light of a desired intensity on the display plane, light modulators in the microdisplay may be configured to direct a combination of the appropriate light intensities onto the display plane. For example, if there is a need to display a light intensity of 19 (binary 10011) in a DMD-based sequential color display system, then a micromirror may be configured to be in the first state (to reflect light onto the display plane) when the color sequence specifies that light intensities of 20, 21, and 24 are provided by the light source. The viewer's visual system may then integrate the three light intensities into a single light intensity of 19.
However, the ordering and duration of the colors displayed in a color sequence may have an impact on the quality of the images being displayed. For instance, if the ordering of the colors in a color sequence is such that the color cycle rate is low, then color separation artifacts may be visible. Additionally, pulse-width modulation artifacts may be visible if durations of blocks of colored light are not well distributed over the entirety of a color sequence. Furthermore, pulse-width modulation artifacts may be visible if the distribution of colors in consecutive color sequences changes dramatically. Both of these artifacts may have a negative impact on the quality of the displayed images.